<— Guild master for 3 years, currently retired from GM’ing but still a member of that guild.
Before doing anything make sure you understand what kind of guild you want to make and why. Is it a PvP guild? A raiding guild? A social guild? Whose friends are in it and why should they come? M+ guild? Competition, hardcore, casual? Time commitment? Etc.
I’ll take my guild as an example: We raid 2 nights a week at Mythic in order to accomodate people who have had a lot of time to raid in the past but, due to various IRL commitments, simply cannot do so any more. That means there’s a lot of “latent skill”, that is we re-unlock experience and potential to play in a high-end but casual manner.
What does that mean? It means we expect good performance and good attendance, however we don’t play all the time so you can have a job and wife and kids on the side, and you should not fear losing your spot due to logging in less - so long as you know how to play.
What do you aim to achieve? We also ways go for all Mythic bosses, but with the caveat that we might not make it - but we’ll get close at the very least!
Once you know what you’re about you need to advertise! People need to know that you exist so they can read about why they should join and how to join.
Advertise on: www.mmo-champion.com
Advertise on: raider.io
Advertise on: wowprogress.com (if you raid)
Advertise on: Guild recruitment on this board - not likely to do much but might as well
Advertise on: trade channel. You can link information about the guild into the trade chat. Use a macro and just click it once or twice whenever you’re in a major city
As Garaidh says, being a guild master can be tough work, so: Delegate, delegate, delegate! Different people are good at different things, and if you trust each other to do what you’re good at each of you, a greater whole will emerge. Make sure you hold regular meetings with your fellow officers (e.g. 10 minutes after raid hours or something twice a week) to update if there are complaints or other issues and to just assess the situation.
Discords can really help tie things together.
And that was basically my entire bucket list. There are a few more things you can do, but doing those things is a very solid foundation.